1. Field of the Invention
The present invention relates to an apparatus for melting a waste product such as a radioactive waste product.
2. Related Art Statement
In a treatment of the radioactive waste contaminated by radioactivity generated from radioactive material handling installations, such as an atomic power plant and the like, it has been well known to increment a combustible waste to ashes and then store the ashes in a suitable place in the installation after placing them in a drum and the like. However, these incinerated ashes are of a powdery granular nature, so that it is desired to stabilize the incinerated ashes and to reduce their volume when the incinerated ashes are filled into the drum for transporting and storing purposes. Such treatment of ashes has been recently studied.
Some methods of treating the radioactive waste have been proposed and the following two methods are typical; namely, a first method in which the radioactive waste or incinerated ashes are solidified by mixing with cement and a second method in which the radioactive waste or incinerated ashes are solidified by mixing with asphalt, plastics and the like.
In the firsrt method of solidfying with cement, however, in order to obtain a solid body having a stable density and strenght by mixing the waste or ashes with cement, it is necessary to add cement to the ashes in a weight of more than 4. Accordingly, there is a disadvantage in that the volume of a treated solid body significantly increases to be more than the volume of ashes and the like to be treated. In the second method of solidfying with asphalt and plastics, it requires pretreatments such as removing and crushing of metal pieces in the waste or incinerated ashes and facilitates for carrying such treatment become complex and large.
Recently, there has been proposed a third method of melting and solidfying the waste and ashes. This third method can effectively remove the disadvantages in the above first and second methods. In the third method, however, the temperature for melting the wastes or incinerated ashes is attained by heating a metal vessel by means of electromagnetic induction. However, the maximum operating temperature is limited to a temperature of 1,000.degree.-1,200.degree. C., so that a melting treatment of waste and the like having a melting point higher than the aforementioned maximum operating temperature is impossible.